Definition
Websterite is ultramafic and ultrabasic rock that consists of roughly equal proportions of orthopyroxene and clinopyroxene. It is a special type of pyroxenite.
Skarns are formed during regional or contact metamorphism and from a variety of metasomatic processes involving fluids of magmatic, metamorphic, and/or marine origin
Origin
Webster, North Carolina
USA, Australia
Discoverer
Unknown
Tornebohm
Etymology
From the town of Webster located in North Carolina
From an old Swedish mining term originally used to describe a type of silicate gangue or waste rock.
Class
Igneous Rocks
Metamorphic Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Hard Rock
Other Categories
Coarse Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock
Texture
Clastic, Granular, Phaneritic, Porphyritic
Earthy, Mud-rich, Rough
Color
Black to Grey, Bluish - Grey, Dark Greenish - Grey, Green, Light Greenish Grey
Black, Brown, Green, Grey, White
Durability
Durable
Durable
Scratch Resistant
Yes
Yes
Appearance
Layered, Banded, Veined and Shiny
Dull
Interior Uses
Countertops, Decorative Aggregates, Entryways, Floor Tiles, Flooring, Interior Decoration
Decorative Aggregates, Entryways, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
As Building Stone, As Facing Stone, Garden Decoration, Paving Stone
Other Architectural Uses
Curbing
Curbing
Construction Industry
As Dimension Stone, Building houses or walls, Cement Manufacture, Construction Aggregate, for Road Aggregate
As a Flux in the Production of Steel and Pig Iron, As a Sintering Agent in Steel Industry to process Iron Ore, As Dimension Stone, Gold and Silver production, Manufacture of Magnesium and Dolomite Refractories
Antiquity Uses
Artifacts
Artifacts, Monuments, Sculpture
Commercial Uses
Cemetery Markers, Commemorative Tablets, Creating Artwork, Laboratory bench tops, Jewelry, Sea Defence, Tombstones
Creating Artwork, Gemstone, Jewelry, Metallurgical Flux, Source of Magnesia (MgO)
Types
Ultramafic rock
Endoskarns
Features
Generally rough to touch, Is one of the oldest rock
Host Rock for Lead, Zinc and Copper Deposits
Archaeological Significance
Formation
Websterite can be formed as cumulates in ultramafic intrusions by accumulation of pyroxene crystals at the base of the lava chamber.
Due to change in environmental conditions, rocks are heated and pressurized deep inside the Earth's surface. Skarn is formed from the extreme heat caused by magma or by the intense collisions and friction of tectonic plates.
Mineral Content
Amphibole, Augite, Bronzite, Chromite, Diopside, Enstatite, Garnet, Hornblende, Hypersthene, Magnetite, Pyroxene
Calcite, Enstatite, Epidote, Garnet, Magnetite, Pyroxene, Titanite
Compound Content
Aluminium Oxide, CaO, Chromium(III) Oxide, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Sulfur Trioxide
Au, CaO, Carbon Dioxide, Cu, Fe, MgO
Types of Metamorphism
Burial Metamorphism, Impact Metamorphism
Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism
Types of Weathering
Biological Weathering, Chemical Weathering, Mechanical Weathering
-
Types of Erosion
Chemical Erosion, Coastal Erosion, Glacier Erosion, Water Erosion, Wind Erosion
-
Grain Size
Coarse Grained
Fine Grained
Fracture
Uneven
Irregular
Streak
White, Greenish White or Grey
Light to dark brown
Porosity
Less Porous
Less Porous
Luster
Dull to Vitreous to Submetallic
Waxy and Dull
Specific Gravity
3.2-3.5
2.86
Transparency
Opaque
Opaque
Density
3.1-3.6 g/cm3
2.8-2.9 g/cm3
Resistance
Impact Resistant, Pressure Resistant, Wear Resistant
Heat Resistant
Deposits in Eastern Continents
Asia
India, Russia
China, India, Russia, Saudi Arabia, South Korea, Sri Lanka
Africa
South Africa
South Africa, Western Africa
Europe
Germany, Greece, Italy, Scotland, Turkey
United Kingdom
Deposits in Western Continents
North America
Canada, USA
Canada
South America
Brazil, Colombia, Venezuela
Brazil, Colombia, Paraguay
Deposits in Oceania Continent
Australia
New Zealand, Queensland
Central Australia, Western Australia
Websterite vs Skarn Characteristics
Though some rocks look identical, they have certain characteristics which distinguish them from others. Characteristics of rocks include texture, appearance, color, fracture, streak, hardness etc. Websterite vs Skarn characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Websterite and Properties of Skarn. Learn more about Websterite vs Skarn in the next section. The interior uses of Websterite include Countertops, Decorative aggregates, Entryways, Floor tiles, Flooring and Interior decoration whereas the interior uses of Skarn include Decorative aggregates, Entryways and Interior decoration. Due to some exceptional properties of Websterite and Skarn, they have various applications in construction industry. The uses of Websterite in construction industry include As dimension stone, Building houses or walls, Cement manufacture, Construction aggregate, For road aggregate and that of Skarn include As a flux in the production of steel and pig iron, As a sintering agent in steel industry to process iron ore, As dimension stone, Gold and silver production, Manufacture of magnesium and dolomite refractories.
More about Websterite and Skarn
Here you can know more about Websterite and Skarn. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Websterite and Skarn consists of mineral content and compound content. The mineral content of Websterite includes Amphibole, Augite, Bronzite, Chromite, Diopside, Enstatite, Garnet, Hornblende, Hypersthene, Magnetite, Pyroxene and mineral content of Skarn includes Calcite, Enstatite, Epidote, Garnet, Magnetite, Pyroxene, Titanite. You can also check out the list of all Igneous Rocks. When we have to compare Websterite vs Skarn, the texture, color and appearance plays an important role in determining the type of rock. Websterite is available in black to grey, bluish - grey, dark greenish - grey, green, light greenish grey colors whereas, Skarn is available in black, brown, green, grey, white colors. Appearance of Websterite is Layered, Banded, Veined and Shiny and that of Skarn is Dull. Properties of rock is another aspect for Websterite vs Skarn. The hardness of Websterite is 7 and that of Skarn is 6.5. The types of Websterite are Ultramafic rock whereas types of Skarn are Endoskarns. Streak of rock is the color of powder produced when it is dragged across an unweathered surface. The streak of Websterite is white, greenish white or grey while that of Skarn is light to dark brown. The specific heat capacity of Websterite is 0.79 kJ/Kg K and that of Skarn is 0.92 kJ/Kg K. Depending on the properties like hardness, toughness, specific heat capacity, porosity etc., rocks are resistant to heat, wear, impact, etc.Websterite is impact resistant, pressure resistant, wear resistant whereas Skarn is heat resistant.